Transmission Control Module (TCM) Communication Circuit
There is an issue with the communication circuit for the Transmission Control Module.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The computer can't talk to the Transmission Control Module like it should. This could be due to bad wiring or an unplugged connector, making it harder for the car to know what's going on with the transmission.
What the computer is actually seeing
The TCM is not responding, or the signals are outside of the expected range when the PCM requests communication.
What a healthy reading looks like
TCM communication should show active data between 0.5 and 2.5 volts on the communication line. If no activity is detected for over 2 seconds, this code is set.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Inspect wiring and connectors between the PCM and TCM for damage or corrosion. Repair if needed.
- 2Check the voltage supply to the TCM, which should be around 12V with the key on. Replace fuse if necessary.
- 3Use a scan tool to monitor TCM communication. If no data is received, consider swapping the TCM with a known good unit. If communication resumes, replace the TCM.
Common causes
- Damaged wiring or connectors between PCM and TCM
- Faulty Transmission Control Module
- Power supply issue to TCM
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's drivable but can lead to erratic shifting or other transmission issues. Fix it soon.
Will this code come back after clearing it?
If the underlying issue isn't fixed, yes, it will likely return.
Why does this code show up with U0101?
U0101 indicates a loss of communication with the TCM, which ties directly into the C1462 code.
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